Well I don't have any hard evidence, its just what we see. ASPM and other power management settings are usually hidden in the BIOS on these Direct from China appliances, if the BIOS is modified to show these, often it makes little difference.
We know for a fact that all recent Intel SoCs can idle at a few watts. I have a 6 port i7 7700U network appliance that idles at 4 watt, no messing around needed. My 10th gen i7 laptop, even with the screen on a low brightness setting can idle at 5 watt, and screen off 2 to 3 watts. Hardkernel who do the Odroid devices can idle at a few watts with an N100. Yet almost universally, these direct form China appliances all seem to idle at 10 to 12 watts or sometimes more.
There should be no reason that just putting in some memory and an NVMe drive (that is known to support ASPM) should have any driver issues.
Granted there may be other things in play, such as poor VRM design which means the devices are not stable jumping in and out of low power states, so they've hard disabled some low power states. Either way, these direct from China devices are flawed, the manufacturers don't really care if they work optimally or not, some even ship them with Intel engineering samples! Like I say, caveat emptor.
